Hong Kong goes underground for new data center caves

Building data centers above ground is cost prohibitive.

With more than seven million people squeezed in to around 1,100sq km of land space—and property prices regularly ranking among the highest in the world—Hong Kong realizes it needs to get inventive if the city wants to attract more big IT business. The answer: cavernous underground data centers that remain naturally cool.

Plans are already in motion to start digging deep according to Cordells property law firm partner Hilary Cordells, reports The Register.

"Rock cavern development can be done, and datacentre use is a particularly good one," she said at the Datacentre Space Asia Conference this week. "It's on the government's radar screen and it's taking active steps but it's not easy and some sites will be more suitable than others."

According to a feasibility study by the special administrative region's (SAR) Civil Engineering and Development Department and engineering firm Arup, two-thirds of the land space in the region have a "high to medium suitability" for cave-digging. Five regions more than 20 hectares (over 49 acres) large have been homed in on as ideal starting points. Arup's report went on to say 400 government facilities have already been identified as possessing the "potential for rock cavern development," so it might not just be data centers taking the journey down under. In fact, the report suggests a whole raft of potential other uses, including cave research labs, rail maintenance depots, or even crematoriums. For scientific research or secret government projects, cave bases make sense given their indiscreet and secure nature. (Just ask Bruce Wayne.)

The report does acknowledge the environmental disruption such a drastic measure would cause but argues that it's been done sensitively before, citing Tai Lam Country Park where a train tunnel runs underneath (the local ecology was saved, with trees replanted etc). It also refers to successful, mainly leisure-based, international projects including Norway's incredible Gjøvik Mountain Hall. (That sounds a lot like a dwarf kingdom but is in fact a sports and music venue accommodating 5,500 people.)

Hong Kong is well known for its banking sector, but the city has been attracting more and more IT business in recent years. Clearly, it wants a chunk of the market share in the region. This year Hong Kong is hosting the first International IT Fest, which is being used as a forum for IT businesses to see Hong Kong's skills, infrastructure, and handy vicinity to mainland China. "We have a very good legal and banking system, good IP protection, free flow of information and few natural disasters—this is the competitive advantage Hong Kong can offer," the government's chief information office Daniel Lai told The Register last year about announcing financial incentives for IT companies converting disused factories into datacentres.

However, with land and property prices being among the highest in the world, Hong Kong is not exactly the obvious choice for moving a data-heavy business—hence the underground burrowing. As such, the government is not expected to be in involved with repurposing the land. According to the Arup report, the government's "hands off" approach to business means the weight of responsibility lies with the private sector. "To generate interest and involvement from the private sector, incentives would be required to make the developments attractive," reads the report, "the incentives could comprise preferential land premiums, enhanced development potential or tax incentives."

43 Reader Comments

Doesn't heat still have to be dissipated somehow? If you store the heat in the rocks, it will eventually become a giant heat dam. People in cold climates have looked at the idea of storing solar heat in the ground in the summer and than pumping the heat out in the winter...

As someone who was born in HK and moved to UK, I want to mention a tibit about how densely populated Hong Kong is. 1100 sq km sounds a lot. It is just little smaller than the size of London, and London is huge!

Many think Hong Kong is nothing but a concrete jungle of sky scrappers, actually it is over 60% green area. A lot of land area is too hilly for buildings and the rest spread on fragmented outlying islands. Because of this, the population density is higher than the figure 6500/sq km would suggest. I'd imagine this is perfect terrain for cave digging.

I'd recommend anyone visiting to not just do shopping round the cities. there are plenty of places of natural beauty. For example, there is Giants causeway twin to that in Northern Ireland, the famous Mai Po bird sanctuary (depending on migratory bird seasons) and the vast Sai Kung country parks.

On topic, there is also a good geological reason why Hong Kong is great for IT data centers. Major internet bankbone in form of submarine cables runs through Hong Kong.

P.S. Somehow I think a better and cost effective way to cool data center is to use sea water, and HK has plenty for obvious reasons. We even use sea water to flush toilets.

I can't imagine being underground is cheap? Sounds crazy expensive to me. But what do I know... I grew up where you had to ride your bike for half an hour to visit the kids next door (outback Australia).

Quote:

Doesn't heat still have to be dissipated somehow? If you store the heat in the rocks, it will eventually become a giant heat dam.

I don't think they generate much heat, certainly nothing compared to other industries.

It's expensive because you need to keep the air temperature lower than the outside air (in summer).

Just pumping it into the air on the surface would probably be fine, but you could get inventive and use it for something useful.

Being underground would create a stable temperature all year round — that's a big logistics win.

Not to be pedantic or anything, but if you have to dig it out completely, it by definition ain't a cave. A cave is a "natural underground space." If you dug it out, it's a tunnel, bunker, basement, or whatever non-cave thing you want to call it.

This doesn't make much sense. The ostensible reason for these data centers doesn't exist anymore. The allure of Hong Kong was that it was integrated economically with China but politically separate. That's not true anymore.

The only use is for high-frequency trading or other inanity that measures latency in meters. But, then, again these companies make so much money that they don't have the same cost concerns.

It would be far, far too expensive and complicated for regular data centers.

As someone who was born in HK and moved to UK, I want to mention a tibit about how densely populated Hong Kong is. 1100 sq km sounds a lot. It is just little smaller than the size of London, and London is huge!

Many think Hong Kong is nothing but a concrete jungle of sky scrappers, actually it is over 60% green area. A lot of land area is too hilly for buildings and the rest spread on fragmented outlying islands. Because of this, the population density is higher than the figure 6500/sq km would suggest. I'd imagine this is perfect terrain for cave digging.

I'd recommend anyone visiting to not just do shopping round the cities. there are plenty of places of natural beauty. For example, there is Giants causeway twin to that in Northern Ireland, the famous Mai Po bird sanctuary (depending on migratory bird seasons) and the vast Sai Kung country parks.

On topic, there is also a good geological reason why Hong Kong is great for IT data centers. Major internet bankbone in form of submarine cables runs through Hong Kong.

P.S. Somehow I think a better and cost effective way to cool data center is to use sea water, and HK has plenty for obvious reasons. We even use sea water to flush toilets.

Ocean water can be corrosive and expensive to plumb and maintain. I would think a heat exchange with ocean water with a glycol coolant would be better.

For serving the Chinese market - sure. Data centers in Hong Kong make sense, but as another poster already mentioned - it's under the control of a regime that's as against the free flow of information as vehemently as the U.S. is against piracy. It seems a bad choice to store large quantities of information, especially anything sensitive.

As someone who was born in HK and moved to UK, I want to mention a tibit about how densely populated Hong Kong is. 1100 sq km sounds a lot. It is just little smaller than the size of London, and London is huge!

Many think Hong Kong is nothing but a concrete jungle of sky scrappers, actually it is over 60% green area. A lot of land area is too hilly for buildings and the rest spread on fragmented outlying islands. Because of this, the population density is higher than the figure 6500/sq km would suggest. I'd imagine this is perfect terrain for cave digging.

I'd recommend anyone visiting to not just do shopping round the cities. there are plenty of places of natural beauty. For example, there is Giants causeway twin to that in Northern Ireland, the famous Mai Po bird sanctuary (depending on migratory bird seasons) and the vast Sai Kung country parks.

On topic, there is also a good geological reason why Hong Kong is great for IT data centers. Major internet bankbone in form of submarine cables runs through Hong Kong.

P.S. Somehow I think a better and cost effective way to cool data center is to use sea water, and HK has plenty for obvious reasons. We even use sea water to flush toilets.

The large amount of green space and stuffs is good an all, but that maintains an artificially high land cost meaning most normal people have to rely on government funded housing or rent really small apartments. The government is even considering reclaiming land rather than opening the interior green space (sorta of a lose/lose scenario [lose green space for cheaper land or have expensive land for more green space]).

It would be interesting to see these caves in action.

The HK gov. leans closer and closer to that of China in limiting civil liberties.

How geologically stable and prone to flooding (including tsunami's) is Hong Kong? If neither is a problem I don't see any serious risks with putting datacenters underground near the coast. Regardless, fiber channel is fast and can cover great distances so it's rather easy to connect a disaster recovery site in case something does go wrong. Given the money that we're talking about, a measly backup datacenter shouldn't be a problem, right?

How geologically stable and prone to flooding (including tsunami's) is Hong Kong? If neither is a problem I don't see any serious risks with putting datacenters underground near the coast. Regardless, fiber channel is fast and can cover great distances so it's rather easy to connect a disaster recovery site in case something does go wrong. Given the money that we're talking about, a measly backup datacenter shouldn't be a problem, right?

HK is prone to flooding in certain areas. Dunno about tsunami's though

I think a cave datac enter with an above ground back up [with tons of power] would be best to avoid the NY scenario

Kansas City has had data centers in massive mined caves for years. They are like underground cities with railroad lines, streets, intersections, stoplights and storefronts - nothing quite like it in rest of world, including Hong Kong. They are naturally 65-70 degrees year round so less power to keep cool. The largest one has 50Msqft of 'office/retail/warehouse/data center' space with 7 miles of roads, a few miles of rails. There are other 'cave cities' in KC area, but this is the largest underground leasable space in world and still mining/growing...

With Google Gbit for consumers in KC, over a dozen longhaul providers (a couple with direct hops to Europe/Asia), Verizon focusing on 100/300Gb longhaul Internet backbone links to KC (only a few cities in US), the KC caves are something to check out. The Hong Kong story is old hat in KC, which has been doing it for 30 years.

edit: yeah if this sounds like an ecodev promo, is because it basically is... fairly unique in world, so have pointed it out as most have no idea.

All those "Intel Inside" stickers are sure to confuse the hell out of the apes who will find these underground datacenters in 1965 years. Because everyone knows monkeys prefer RISC-based architectures. GODDAMN YOU ALL TO HELL!

How geologically stable and prone to flooding (including tsunami's) is Hong Kong? If neither is a problem I don't see any serious risks with putting datacenters underground near the coast. Regardless, fiber channel is fast and can cover great distances so it's rather easy to connect a disaster recovery site in case something does go wrong. Given the money that we're talking about, a measly backup datacenter shouldn't be a problem, right?

HK is prone to flooding in certain areas. Dunno about tsunami's though

I think a cave datac enter with an above ground back up [with tons of power] would be best to avoid the NY scenario

There never had been tsunami in Hong Kong. Flooding was more due to heavy rain more than any river banks. Certainly flooding would be a concern for caves, but civil engineering expertise in HK is almost second to none in the world and I am sure they can go round it.

Hong Kong has a separate government from China and the internet there is totally unlimited. HK residents can freely protest both their government & the mainland China government -- hell, protesting seems to be a second job for many of them. The only part mainland China currently controls is military & foreign affairs (e.g. HK embassy/consulate duties handled by China).

Supposedly, the governments of HK and mainland China will fully integrate in 2048 but by that time, everybody will have datacenters up their butts.

Hong Kong has a separate government from China and the internet there is totally unlimited. HK residents can freely protest both their government & the mainland China government -- hell, protesting seems to be a second job for many of them. The only part mainland China currently controls is military & foreign affairs (e.g. HK embassy/consulate duties handled by China).

Supposedly, the governments of HK and mainland China will fully integrate in 2048 but by that time, everybody will have datacenters up their butts.

Kansas City has had data centers in massive mined caves for years. They are like underground cities with railroad lines, streets, intersections, stoplights and storefronts - nothing quite like it in rest of world, including Hong Kong. They are naturally 65-70 degrees year round so less power to keep cool. This one alone (link below) is 50Msqft of 'office/retail/warehouse/data center' space with 7 miles of roads, a few miles of rails and there are other 'cave cities' in KC area, but this is the largest underground leasable space in world and still mining/growing...

With Google Gbit for consumers in KC, over a dozen longhaul providers (a couple with direct hops to Europe/Asia), Verizon focusing on 100/300Gb longhaul Internet backbone links to KC (only a few cities in US), the KC caves are worth checking out. The Hong Kong story is old hat in KC, which has been doing it for 30 years.

This ad brought to you by the KC tourism board.

Yeah, people have been building underground for literally centuries. I suspect if you look around the world many more places will be found. Maybe the next question should be is just how many data centers does a nation need?

^Well, a shameless economic development 'promo' if anything, not tourism - because it is not only true, it's fairly unique in the world. There aren't many places in world doing it, especially that also have 100/300Gb connections, direct hops to both sides of pond as well as Google rolling out cheap Gbit to residents. KC's commercial caves really are the largest in world and have been commercialized for a few decades. They have mastered the ventilation taking clues from chambers of ants and meerkats. Nothing wrong with pointing that out.

With cloud computing/gaming/storage just now taking baby steps and corporations wanting 24x7 hotsite redundancy to other locations, data centers are barely taking off. US Data Centers use about 2-4% power today, expected to hit 10-15% in 10 more years - caves can help cut the power costs. And then when Skynet comes online...

The question is whether you want to target the Chinese population to make money. If you have no interest in trying to make money in Asia, this story is only of passing technical interest to you. But if you do want to make money in China, you have to locate your datacenters somewhere in Asia where your target consumers have low latency access. And you have to play by the local rules which are comparatively more strict/more corrupt in mainland China versus Hong Kong SAR (or Macau SAR).

If the rules turn you off, don't participate in the markets there. But that's an option for you as a resident of the western world. Those holding passports of countries in Asia often don't have that choice so they have to decide whether spending more money for an underground Hong Kong batcave is worth the extra flexibility (for the near future).

The question is whether you want to target the Chinese population to make money. If you have no interest in trying to make money in Asia, this story is only of passing technical interest to you. But if you do want to make money in China, you have to locate your datacenters somewhere in Asia where your target consumers have low latency access. And you have to play by the local rules which are comparatively more strict/more corrupt in mainland China versus Hong Kong SAR (or Macau SAR).

If the rules turn you off, don't participate in the markets there. But that's an option for you as a resident of the western world. Those holding passports of countries in Asia often don't have that choice so they have to decide whether spending more money for an underground Hong Kong batcave is worth the extra flexibility (for the near future).

Yet people still flock the streets to protest mainlanders buying too much baby milk powder.The thing is, if you want people to take you seriously, you shouldn't storm the streets for every single little hindrance to your life. The HK people are good and free now - just about as free as anybody on this planet. (http://www.heritage.org/index/) Most of the negative press towards mainland China is simply caused by HK citizens trying to find bones in scrambled eggs.

Doesn't heat still have to be dissipated somehow? If you store the heat in the rocks, it will eventually become a giant heat dam. People in cold climates have looked at the idea of storing solar heat in the ground in the summer and than pumping the heat out in the winter...

For serving the Chinese market - sure. Data centers in Hong Kong make sense, but as another poster already mentioned - it's under the control of a regime that's as against the free flow of information as vehemently as the U.S. is against piracy. It seems a bad choice to store large quantities of information, especially anything sensitive.

Could have been wrote:

For serving the Chinese market - sure. Data centers in Hong Kong make sense, but as another poster already mentioned - it's under the control of a regime that's as against the free flow of information as vehemently as the U.S. is against privacy. It seems a bad choice to store large quantities of information, especially anything sensitive.

1. The amount of heat generated by a large datacentre is not at all small. In the case of real Google-sized data centres, it is so huge that they need to be sited near rivers for the primary cooling loop. This is a fundamental feature of computation: the minimum power consumption is proportional to the product of processing rate x (core voltage)². (In practice, inefficiencies cause it to be somewhat larger.) Every now and again, a new core technology enables the core voltage factor to be reduced, but inbetween times, every increase in processing power results in an increase in waste heat output. So when the processing rates are measured in petaflops, the heat ouput is huge.

2. When underground, even moderate rates of heat emission eventually become a serious problem unless there is a significant cooling system. For example, the London underground is heated mainly by human body heat. It is cooled partly by air pumping by the trains, and partly by conduction into the surrounding earth. But after more than a century of body heat being conducted into the earth, it is now darn hot; too hot for air pumping by trains to provide comfort, and they are having to install powered cooling systems.

3. The chairman of the 2nd biggest bank in HK is a communist party official; two of the biggest telecoms providers in HK are state-owned corporations or subsidiaries of them; the (undemocratic) election system has been rigged so that increasingly many communists are elected despite their widespread unpopularity; massive protests against the "moral and national education plan" (widely seen as communist brain washing for youth) saw PLA armoured vehicles patrolling the streets (even though it theoretically violates the Basic Law) and the implementation of the new curriculum only delayed; and so on and so forth. You can quibble all you like about exactly how much influence the CPC has in Hong Kong. The fact is, they have a lot, and with the now overwhelming evidence that so much corporate hacking worldwide is conducted by the PLA, you would have to be a complete idiot to "protect" your data by moving it to Hong Kong.

3. The chairman of the 2nd biggest bank in HK is a communist party official; two of the biggest telecoms providers in HK are state-owned corporations or subsidiaries of them; the (undemocratic) election system has been rigged so that increasingly many communists are elected despite their widespread unpopularity; massive protests against the "moral and national education plan" (widely seen as communist brain washing for youth) saw PLA armoured vehicles patrolling the streets (even though it theoretically violates the Basic Law) and the implementation of the new curriculum only delayed; and so on and so forth. You can quibble all you like about exactly how much influence the CPC has in Hong Kong. The fact is, they have a lot, and with the now overwhelming evidence that so much corporate hacking worldwide is conducted by the PLA, you would have to be a complete idiot to "protect" your data by moving it to Hong Kong.

And exactly which biggest telecoms are you talking about? Fixed line phone? Internet? Mobile? All owned by private coroporations, unless you count China Mobile. The four biggest internet providers in HK are Hutchison, owned by Li Ka Shing, 8th richest man in the world, Netvigator, owned by Mr Li's son, iCable, owned by Wharf, a local conglomerate, and HKBroadband owned by CVC Capital Partners, a UK based Private Equity Firm. Exactly how is that state owned?

As to your other statement re PLA armoured vehicles patrolling the streets of HK? I'd like to see your source - and linking to Epoch Times, a mouthpiece of the Falun Gong is not a reliable source, BBC or CNN pls. I live in HK and the PLA is permanently confined to barracks, soliders are not even allowed off barracks lest they be "corrupted" by our capitilsm.

Back on topic. There are plenty of underground bunkers constructed by the British prior to WW2 scattered around HK that could be used as data centres, some even located 5min from the CBD. Sea water is also readily available to be used for cooling, with many HVAC systems for office towers cooled via sea water. But yes, I can see this being debated to death or worse, being subsidised by the government like our "Cyberport" which was supposed to be a tech start up hub but ended up a massive luxury housing development and shopping mall with token offices rented to such up and coming start ups like Microsoft and IBM.